1. Technology Field
The present invention relates to a method of dynamically switching partitions for a memory card, and a memory card controller and a memory card storage system using the same.
2. Description of Related Art
Digital cameras, cells phones, and digital music players have undergone rapid growth in recent years, so that consumer demand for storage media has also rapid increased. Rewritable non-volatile memory is one of the most adaptable memories for such battery-powered portable products due to its characteristics such as data non-volatility, low power consumption, small volume, and non-mechanical structure. A memory card is a storage device adopting NAND flash memory as storage medium. A memory card has been broadly used for storing important personal data thanks to its small volume and large capacity.
The volume of a storage device adopting NAND flash memory as storage medium is very small, and therefore a risk of losing the storage device is relative higher. In order to prevent important data stored in this kind of the storage device from being read by a un-authorization user due to a loss of the storage device, several encryption or authentication techniques are developed for protecting the important data stored in the storage device. For example, taking a flash drive as an example, the memory of the flash drive can be divided into a general partition and a security partition, wherein a user accesses data stored in the security partition only after the user has passed an identification authentication. Accordingly, the user can select to only use the general partition or pass the identification authentication for using the security partition according to his/her desire. However, according to the standard of a memory card (e.g., a secure digital (SD) memory card and a multi media card (MMC), etc.), the memory card can not support the function for a plurality of partitions. Namely, the storage spaces of the memory card can not be formatted into a plurality of partitions for accessing by a host system. Accordingly, the storage spaces of the memory card only are formatted into one partition and a data protect function (i.e., a write protect mode) of the memory card is started or not with the entire partition. Therefore, in order to protect some important data, a user of a memory card must set the storage mode of the entire partition of the memory card into the write protect mode, so that the user is requested to pass the identification authentication whenever his/her is about to use the memory card and thus it causes inconvenience for using. Thereby, how to implement a plurality of partitions in a memory card is one of the major subjects in the industry.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.